The invention disclosed herein is an improvement over the invention disclosed in applicant's U.S. Pat. No. 4,759,129, issued July 26, 1988, which patent is incorporated by reference herein.
Applicant's prior U.S. patent discloses a pencil sharpener designed to sharpen pencils of elongated cross section. The sharpener disclosed therein accomplishes this feat by providing two pairs of cutters wherein each cutter defines only a portion of the circumference of a circle. As one pair of cutters is engaging to sharpen surfaces engaged thereby, the other pair of cutters is indexed away from engagement with the pencil.
Through the use of the teachings of the pencil sharpener disclosed in applicant's prior U.S. patent, effective sharpening of a pencil of elongated cross section may be accomplished, however, since each cutter is only in engagement with the pencil which is being sharpened for about one third of every revolution, sharpening of a pencil using the teachings of applicant's prior patent may be relatively time consuming.
As such, a need has developed for a pencil sharpener which may be used to sharpen pencils of elongated cross section, which pencil sharpener includes cutter blades which will sharpen the surfaces of the pencil continuously during revolution of the cutter blades.